Cut the fat into the flour mix. The basic idea is to keep handling to the minimum to avoid stringy gluten protein formation. Refrain from working with your hands in order to prevent the fat from melting. This would make the dough hard to work with and it may fall apart. Instead, use a manual pastry blender or pair of knives in a scissor motion. You want to incorporate the fat particles into the flour mix. The fat will lubricate the flour granules and consequently form a discontinuous, granular texture. This in turn will discourage gluten protein from forming, once liquid is added, in order to make dough. Cutting is done when the texture resembles corn meal or rough bread crumbs.